Much research exists to support the efficacy of combinations of stimulant medication and behavior therapy to treat the social, behavioral, and learning problems of children with Attention Deficit-Hyperactivity Disorder. However, little is known about what Whalen and Henker have called the "emanative effects" of these two treatments; that is, the unintended and often unrecognized effects of treatment on cognitive constructs and causal attributions. One aspect of such emanative effects involves children's self-evaluations of treatment; specifically, are children aware of treatment gains, does the accuracy of their perceptions of improvement vary across treatment modalities and behavioral domains, and do their perceptions effect their liking of these treatments? A related set of questions involves the attributions children make regarding treatment gains--do children make different , attributions to improvements generated by methylphenidate as opposed to behavior therapy? How do different treatments and children's attributions about their performance related to those treatments effect their subsequent performance? The proposed project requests funding for two related studies to examine the effects of methylphenidate and behavior therapy on the treatment-related perceptions and attributions of ADHD children. In the first, children will be asked to evaluate their social, behavioral, and learning performance under three medication (placebo, low dose, high dose) and two behavior therapy (behavior therapy, no behavior therapy) treatment conditions; these self-perceptions of performance will be compared to objective evaluations of performance to examine the accuracy of children's self-perceptions under various treatment conditions and across various domains. In the second study, children will be asked to perform a reaction time task under three medication (placebo, low dose--.3 mg/kg, and no medication), two behavior therapy (reward, n ' o reward), and two manipulated feedback (high success, low success) conditions, complete evaluations of their attributions regarding their performance, and then perform a second trial of the reaction time task. In Study 2, the effect? of treatment on children's attributions toward performance and the effects of treatment and attributions on subsequent performance will be examined.